Are you having trouble starting your Mac? Do you want to create a bootable USB on macOS to resolve the problem with your system? You've come to the right place.
A bootable USB drive can help you install or reinstall OS X on your Mac or even run a diagnostic tool without any internet connection or access to the Mac App Store.
In this article, we'll discuss how to create a bootable USB on macOS, what its requirements are, and how you can get macOS installer files. We'll also explore how to use Terminal to create a USB installer and boot your Mac using the created installer.
Part 1. What Do You Need to Create a Bootable Installer
To create a bootable macOS USB, you'll need a few things to get started:
- Mac OS X File: A downloaded installer for macOS Catalina, Big Sur, High Sierra, or El Capitan. You can get the OS installation file from Software Update in System Preferences or Mac App Store.
- A USB flash drive: You need to use a blank USB flash drive with at least 14GB of storage space. However, you can also use any other secondary volume formatted as Mac OS Extended.
- Back-Up Your Data: Make sure to back up your data on the USB drive before starting the process. So that when it is formatted, you don't lose any data.
Part 2. How to Get macOS Installer Files
To create a bootable installer, you need to download the files from the Apple website. Afterward, follow the steps below to get the installer files you need for a different macOS.
Step 1: Select the required macOS from the table below:
Step 2: You will be directed to Apple's website. Click "View in Mac App Store" and select the "Open App Store" option from the prompt.
Step 3: In the Mac App Store, click the "Get" button to download the macOS Installer. Once the downloading process is complete, the installer file will be stored in the Application folder as an app named Install macOS X (X here will be replaced with the OS you've downloaded).
Part 3. Use Terminal to Create the USB Installer
Before creating a bootable USB on macOS, we have listed the commands for different macOS versions you will use in the process:
The "createinstallmedia" Command for Various macOS Versions
Depending on the macOS version, the 'createinstallmedia' command in the Mac Terminal can be a little different, as you’ll observe below:
- Catalina macOS users can type the “sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume” command.
- If you are using Big Sur, type the “sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume” command in the Terminal.
- High Sierra macOS users can use this command: sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume.
- Mojave macOS users can use the following command in the Terminal: sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume.
Note: Make sure to replace "My Volume" with your drive name.
Steps to Create the USB Installer
Now, please follow the steps below to create the USB installer:
Step 1: Connect the USB drive to your Mac system. Press the Command key + Space bar, type Disk Utility, and launch it.
Step 2: If you are using High Sierra or later macOS versions, click the "View" option on the top left side of the screen, and from the drop-down menu, choose Show All Devices.
Step 3: In the sidebar, choose the USB drive or any other external drive you are using. Make sure to select the root drive. Now, click "Erase," and in the Erase prompt window, choose Mac OS Extended (Journaled) as the format. Next, select GUID partition map as the scheme and click "Erase."
Note: You can also rename your USB drive name.
Step 4: Wait for the Disk Utility to create the partition and set up the USB drive. Click the "Done" option.
Step 5: Head to Applications > Utilities and launch the Terminal. You can also press Command + Spacebar and type Terminal to find and open it.
Step 6: Now, copy the createinstallmedia command that corresponds to the macOS version you want to install, replace "My Volume" with the USB drive name and press the "Enter/Return" key.
Step 7: Afterward, type the Admin password and hit the "Enter/Return" key. You will see this message appear: "To continue we need to erase the volume at /Volume/Untitled," press Y and press Enter. Wait for the process to show 100%.
Step 8: The Terminal will start copying the macOS installer file on your USB after formatting everything on it. Once the copying process is complete and Done appears in the Terminal panel, close the Terminal.
Your bootable USB drive is all set, and you can use it to install macOS on any Mac system.
Part 4. How to Boot the Mac Using the Created Bootable USB Drive?
Before booting your Mac system with a bootable USB drive, check whether you are using a Mac with an Apple Silicon chip or an Intel processor. Afterward, follow these instructions in sequence:
For Mac with The M1 Apple Silicon Chip
Step 1: Plugin the bootable USB flash drive into the USB port on your Mac system.
Step 2: Press and hold the Power button on your Mac until the Startup Option displaying bootable volumes appears on the screen.
Step 3: Choose the bootable USB drive and click the "Continue" option. Afterward, follow the on-screen instructions in the macOS installer window.
For Intel-Based Mac Systems
Step 1: Plugin the bootable USB drive into the USB port of your Mac system.
Step 2: On your Mac laptop, press the Power button and hold the Option key until the screen displaying bootable volume options appears.
Note: before continuing, ensure that the "External Boot" setting in the Startup Security Utility is enabled, allowing booting from external media.
Step 3: Choose the bootable USB installer drive volume and click the "Return".
Step 4: Select "Install macOS or OS X" from the Utility window and click "Continue."
Step 5: Follow the on-screen instructions to complete the booting process.
Part 5. How To Recover Data from Unbootable Mac?
If you don't want to or can't reinstall the operating system on your unbootable Mac, you can use recovery software to retrieve your files.
Recoverit is a reliable and effective data recovery program that can help you recover lost or deleted files from your unbootable Mac in the following way:
Things You'll Need
- A blank USB with at least 8 -16 GB of storage space or more.
- Another working Mac computer.
- Recoverit software installed on your working computer.
Steps to use Recoverit to recover your data
Once you have all the things in hand, follow these steps in sequence to recover data from an unbootable Mac.
Step 1: Download the Recoverit software on your working Mac computer/laptop and install it. Once installed, launch the app and head to the "System Crashed Computer" option from the menu. Next, insert the blank USB into the USB port on your PC and click the "Start" option.
Select the USB name and click the "Start" option. Click the "Format" option on the warning screen/message.
Step 2: Plugin the bootable USB drive into your crashed Mac, press the Power button to turn the laptop on, and press the Option key. Select the Wondershare Recoverit Bootable Media Drive on the screen.
Step 3: Afterward, select the copy of the files and plug in an external hard drive into your unbootable Mac. Select the hard drive as the destination and click "Start Copy" to move the file to the connected drive.
Once the copying process is completed, you will get all your data on the external hard drive you've connected to your Mac system.
Video Tutorial- How to Create a Bootable USB with any Mac OS X Version
In this comprehensive guide, we've discussed how to create a macOS bootable USB using the Terminal with simple instructions. We also explored how to get the macOS installer file from the Mac App Store and boot the Mac using the created bootable USB drive. Furthermore, we've provided a step-by-step solution for recovering your data from an unbootable Mac system.
Hopefully, you find this guide helpful and can now create a USB installer without much effort.